<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			/*
			div的高度由line-height决定
			*/
			.a{
				font-size: 16px;
				line-height: 0;
				border: 1px solid red;
				background-color: #00FFFF;
				margin-bottom: 100px;
			}
			.b{
				font-size: 0;
				line-height: 16px;
				border: 1px solid #00B0E7;
				background-color: #999999;
			}
		</style>
	</head>
	<body>
		<div class="a">我是小帅哥</div>
		<div class="b">我是小小怪</div>
	</body>
</html>
